Improvement in reverberatory furnaces



against a low bridge, d2.

" UNITED STATES PATENT OFFICE;

HUGH MCDONALD, OF. PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN REVERBERATORV FURNACES.

Specification forming part of Letters Patent No. 139,683, dated June 10, 1873; application filed February 27, 1873.

To all whom it may concern:

Be it known that I, HUGH MoDoNALD, -of Pittsburg', in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Reverberatory Furnaces; and I do hereby declare the following to `be a full, clear, and exact description` thereof, reference being had to the accompanying drawings, in two sheets, making a part of this specification, in which- `Figure l, Sheet l, is a side elevation of a puddlingfurnace fitted with my improvements. Fig. 2, Sheet 2, shows a longitudinal vertical section thereof. Fig. 3, Sheet 2, is a top or plan view of the coking and combustion chambers and forward beyond the tire-bridge,

the ordinary puddling, boiling, heating, "or

smelting furnace; and consists in the con-h struction and combination of devices for ef- `fecting the more perfect combustion dof the fuel, for the more complete utilization-of `the smoke and gases of combustion, and for supplying heated air, steam, or water to certain parts of the furnace'to secure greaterheat.

-To enable others skilled in the art to make and use my invention, I will proceed" tudescribe its construction and mode of operation.

The furnace shown is of the well-known reverberatory form suitable for the operations `of boiling, puddling, heating, or smelting of metals. The working-chamber A, neck A1, and chimney A2 are ofthe usual construction.` The partin which the combustion of the fuel is effected I divide, by -transverse walls b b',

into three or more chambers, B B1 B2. The lower edges of these walls are about even with or a little below the upper edge of the firebridge a. The usual or any suitable gratebars d are arranged under the chambers B B1, and at their inner ends rest on and abut Under the chamber B2 I arrange transversely across the grate "bars d1, or other suitable grating, for the admission of air to that chamber. This grating is accessible, for cleaning or other purposes, at the side door k, which, in Fig. l, is shown open. v

.i The chambers B B1r are to be charged with coal through the stop-holes Z Z, and as the fuel (usually soft orbituminous coal) becomes` coked, and the smoke andother gasesV are driven off, it is either allowed to be consumed there or, as it reaches an incandescent condi,- tion, it may be worked forward under the wall b into the chamber B2. Or, if so preferred, the fresh fuel may be fed only into the iirst chamber B, and, as it becomes coked, or partially coked, it may be worked forward into the next chamber B1.

In the `sides of the furnacewall at the chamber B2 I arrange driving-lines c c, which take air through holes c1 in the top, and, through sliding registers c2, admit the saine into the chamber B2, the supply being regulated by the adjustment of the registers in the usual way. The smoke and unoonsumed gases pass forward from, the chambers B B1, one or bot-h, into the chamber B2,where air is supplied to promote their combustion, either from below, through the grating d1, or laterally, through the registers c?, or both, as may y The llame passes over` to the. working-chamber A, and does its work in-the be preferred.

usual manner. It is a well-known fact that steam or watery vapor will, in some cases, facilitate materially the combustion of solid or gaseous carbons, if

brought, at the proper temperature, into intimate contact or admixture therewith. To secure the presence and cooperation of such steam or vapor, I arrange on or in any one of the walls ofthe furnace, in the manner substantially as shown on the wall b, a pipe or pipes, e, with suitable jet-holes, as shownfand supply steam or water thereto` by means of a pipe, el, which is connectedwith any suitable heater or steam-generator. The supply is controlled at pleasure by cocks c2. lf steam be introduced, it passes into the line of draft, is brought into intimate contact with the smoke and gases of combustion at a high temperature, and facilitates their combustion iu-accordance with well-known principles. But if water is introduced, the fuel is kept in a under the furnace.

moistened condition, and the moisture is by the heat converted into steam, with the benecial result already mentioned.

As I find it sometimes advantageous to do so, I have devised and shown means for conducting the excess or any desired proportion of the smoke and unconsumed gases from the coking-chamber B (or other coking-cha-mber) to the rebridge by another route. For this purpose I make 011e or more openings, f, in one or both sides of the coking-chamber, and thence by ues f conduct such part of the smoke and gases forward to a gas holder, g, A pipe, g1, opened and closed by adamper or cock, g2, leads from this holder up into the lire-bridge a, which rebridge is so'made that, by a series of jet-holes, s s, or other suitable opening or openings, the smoke may at pleasure be discharged into the path of the flame or heat which passes over the tire-bridge, and there be consumed. I also make on one or more sides of the chimney A2, at its lower end, or what is in effect the same thing, on one or more sides of the neck of the furnace, an outer case, h, inside which air is admitted at the upper end, and from which, after being heated, it is conducted by pipes h1 back along the side of the furnace. The backward ow of heated air is controlled by dampers or cocks h2 h3. At u a side pipe leads into a hollow part, n', of the lire-bridge a, or into a hollow chamber which is built across in close contiguity thereto. Thence it escapes by jet-holes s into the path of the flame so as to unite intimately with the escaping smoke and gases which emerge from the jet-holes s, and thus supply heated oxygen to facilitate their combustion. As another or additional means of securing the same end, I supply steam to the smoke and gases while in the holder g by means of a steam-pipe, t', fitted with a cock, fl', for regulating the flow. In such case the steam is mixed with the Asmoke and gases while in the holder, and, so

intermingled, they escape at the jet-holes s, as already described. The position of all these devices is such that they are kept in a heated state by heat from the furnace. I also supply heated air to the smoke and unconsumed gases which pass forward under the wall b. For this purpose I extend the ue h1 back to a suitable point, where, by a lateral connec tion, 1', it opens into a pipe, r', arranged transversely across the chamber on or near the lower edge of the wall b. This pipe r has also a series ofjet-holes, or other suitable opening or openings, by which the heated air is permitted to escape into the chamber B2, where it unites with the smoke and gases to secure their more perfectcombustion. Instead of heated air, water, heated to near a vaporiz ing temperature, or steam itself, may be introduced into the chamber B2 by the pipe-rf;

and the pipe r may be arranged across the chamber B2 at any other desired point with beneficial result from the air, steam, or water thus introduced. Many of these devices may be separately combined with a furnace with. beneficial result. The number of walls b b may be increased at pleasure, and the steam, water, or hot-air pipes applied to each or all of them, as may be desired. The ash-pitmay have doors It,\or be left open in front, at pleasure.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. In combination with the coking-chamber or furnace, a steam or water pipe suitably arranged therein forl supplying moisture to the smokeand gases evolved in the operation of coking, substantially as set forth.

2. In combination with a series of chambers, B1 B2, two or more in number, a pipe, i", arranged transversely across the chamber B2 at a suitable point for supplying air or steam to the smoke and gases of combustion at or near the point of their entrance into the said chamber, substantially as set forth.

3. In combination with a fuel-coking chamber, B, of a furnace of the class indicated, a

smoke-flue or smoke-fines, j", suitably arranged for conveying any desired portion of the smoke and gases from the coking-chamber out of the line of the draft, and causing them to re-enter again the line of the draft in a separate combustioncham ber, B2, and at or near the fire bridge, either directly or through lan intermediate gas-holder, g, substantially as set forth.

4. The combination of case h, pipe or pipes h1, and chambered fire-bridge, with openings thence into the combustion-chamber B2, substantially as and for the purposes set forth.

5. The combination of the air-openings from the pipe a', and the smoke-openings from the lire-bridge, arranged to discharge in close contiguityinto the path of the llame from the combustion-chamber to the working-chamber, substantially as set forth.

6. The steam-pipe i and smoke-fines j" uniting and leading to the chambered fire; bridge, so as to discharge the smoke and gases of combustion intermingled with steam into the combustion-chamber, the combination being substantially as set forth.

7. The openings c1 in the upper part ot' the chamber B2, and registers c2 for supplying air laterally to the tire in the chamber, substantiallyas set forth.

In testimony whereof I, the said HUGH MCDONALD, have hereunto set my hand.

HUGH MGDONALD.

Witnesses:

A. S. NICHOLSON, G. H. CHRis'rY.

' AL nhrngn 

